A vehicle door mirror in which a mounting hole is provided in a base member mounted on a side door, a boss of a support shaft pivotably supporting a mirror housing is inserted through the mounting hole so that a plurality of ribs provided on the outer periphery of the boss abut against an inner peripheral face of the mounting hole, and the support shaft is fixed to the base member by the base member and the boss being fastened by means of a screw member is known from Patent Document 1.